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9,253 diagnostic guides

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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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All severities9253 Low priority305 Check soon8256 Urgent621

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All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 649–672 of 7353

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P02FADiesel Intake Air Flow Position Sensor Minimum/Maximum Stop PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP02FA relates to diesel intake air flow position sensor minimum/maximum stop performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P02FBCold Start Fuel Injection Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP02FB relates to cold start fuel injection control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P02FCCold Start Fuel Injection Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP02FC relates to cold start fuel injection control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P02FDCold Start Fuel Injection Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP02FD relates to cold start fuel injection control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P02FECold Start Fuel Injection Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP02FE relates to cold start fuel injection control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P02FFPropulsion System Inactive Timer PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP02FF relates to propulsion system inactive timer performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0300Random/Multiple Cylinder Misfire DetectedUrgentEngine Problems30–90 minutesDiagnose P0300 random misfire code. Learn why multiple cylinders are misfiring and the systematic approach to finding the cause.P0301Cylinder 1 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesComplete guide to P0301 cylinder 1 misfire. Find out what's causing the misfire and how to fix it step by step.P0302Cylinder 2 Misfire Detected - Causes & FixesUrgentEngine Problems30–75 minutesComplete guide to P0302 cylinder 2 misfire. Diagnose and fix the misfire with our step-by-step troubleshooting guide.P0303Cylinder 3 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesFix P0303 cylinder 3 misfire code. Learn the common causes and proven solutions for cylinder 3 misfiring.P0305Cylinder 5 Misfire Detected - Causes & FixesEngine ProblemsLearn what P0305 means, why cylinder 5 is misfiring, and how to diagnose and fix it with a clear step-by-step approach.P0306Cylinder 6 Misfire Detected - Diagnosis GuideEngine ProblemsComplete guide to the P0306 cylinder 6 misfire code, including symptoms, common causes, and step-by-step fixes.P0307Cylinder 7 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0307 means Cylinder 7 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0308Cylinder 8 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0308 means Cylinder 8 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0309Cylinder 9 Misfire DetectedCheck soonEngine Problems30–120 minutes for initial diagnosisP0309 relates to cylinder 9 misfire detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P030AIgnition A Control Signal Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030A relates to ignition a control signal circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P030BIgnition A Control Signal Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030B relates to ignition a control signal circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P030CIgnition A Control Signal Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030C relates to ignition a control signal circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P030DIgnition B Control Signal Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030D relates to ignition b control signal circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P030EIgnition B Control Signal Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030E relates to ignition b control signal circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P030FIgnition B Control Signal Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP030F relates to ignition b control signal circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0310Cylinder 10 Misfire DetectedCheck soonEngine Problems30–120 minutes for initial diagnosisP0310 relates to cylinder 10 misfire detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P0311Cylinder 11 Misfire DetectedCheck soonEngine Problems30–120 minutes for initial diagnosisP0311 relates to cylinder 11 misfire detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P0312Cylinder 12 Misfire DetectedCheck soonEngine Problems30–120 minutes for initial diagnosisP0312 relates to cylinder 12 misfire detected. Check the fault conditions and vehicle-specific procedure before replacing parts.